> one solution in linux is to just launch off another thread to do the> io which'll get stuck in kernel mode, not the whole process. but this> is kind of cheesy, and has the overhead of creating a new thread.

Its not much of an overhead - 11uS for the clone and exit. Your I/O willprobably swallow that. You dont have to create a thread for each I/O eitherjust for each currently pending parallel I/O - you can keep a pair offriends around for I/O